Vibratory screen drive belt tensioner systems, methods, and apparatus

ABSTRACT

Tensioner systems, methods and apparatus are described for tensioning drive belts of vibratory screens.

BACKGROUND

Vibratory screens are used to classify material such as aggregatematerial (e.g., sand, stone, gravel, etc.) by one or morecharacteristics (e.g., size, etc.).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a partial side elevation view of an embodiment of a vibratoryscreen.

FIG. 1B is a partial perspective view of the vibratory screen of FIG.1A.

FIG. 2 is a perspective view of an embodiment of a tensioner assembly.

FIG. 3 is a side elevation view of the tensioner assembly of FIG. 2 .

FIG. 4 is a sectional view along section A-A of FIG. 3 .

FIG. 5 is another perspective view of the tensioner assembly of FIG. 2 .

FIG. 6A is a side elevation view of the tensioner assembly of FIG. 2 ina first position.

FIG. 6B is a side elevation view of the tensioner assembly of FIG. 2 ina second position.

FIG. 6C is a side elevation view of the tensioner assembly of FIG. 2 ina third position.

FIG. 7 is a side elevation view of another embodiment of a tensionerassembly.

DESCRIPTION

Referring to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views, FIGS. 1Aand 1B illustrate a vibratory screen 10 (e.g., horizontal screen, etc.)incorporating a tensioning assembly 100. The vibratory screen optionallycomprises a pair of sidewalls 12 operably supporting one or moreclassifying decks (not shown) and an eccentric shaft coupled to thesidewalls 12. Each sidewall 12 is optionally supported on a support rail13. The vibratory screen 10 optionally comprises a vibration system 20(e.g., comprising one or more rotatable imbalanced weights) configuredto vibrate the vibratory screen 10 when driven (e.g., with an eccentricshaft coupled to the sidewalls 12). The vibratory screen 10 optionallycomprises a drive system 40 configured to drive the vibration system 20.The drive system 40 optionally comprises a motor 42 (e.g., electricmotor, diesel motor, etc.) configured to drive a pulley 43 (e.g., drivepulley). The drive system 40 optionally comprises a pulley 46 operablycoupled to vibration system 20 and configured to drive the vibrationsystem 20. The motor 42 is optionally supported on a motor mount 30. Themotor mount 30 optionally comprises one or more supports 32 (e.g.,supports 32-1, 32-2) such as support beams. The supports 32 areoptionally supported by (e.g., mounted to) a support rail 13 and/or asidewall 12. A drive belt (e.g., v-belt which is made of rubber or othersuitable material). The drive belt 44 is optionally tensioned by thetensioning assembly 100 as described herein.

Referring to FIGS. 2-5 , the tensioning assembly 100 is described inmore detail. The tensioning assembly 100 optionally comprises a supportbracket 200, a spring 300 (e.g., torsion spring), and a belt engagementassembly 400.

Support bracket 200 optionally comprises a mounting plate 210 optionallyhaving one or more openings 212 for mounting the support bracket 200 tothe vibratory screen 10 (e.g. to the support 32-1 or other structuralmember of the motor mount 30, etc.). The support bracket 200 optionallycomprises one or more side plates 220 (e.g., side plates 220-1, 220-2).One or more side plate 220 optionally comprise an opening 223 forpivotally coupling an adjustment arm 230 to the side plate 220 (e.g., bya pivotal coupling 225). The adjustment arm 230 optionally comprises anopening 238 or other feature for coupling a tool (e.g., breaker bar,etc.) to the adjustment arm 230 in order to increase the torque appliedto the adjustment arm 230 by an operator. One or more adjustment plates240 (e.g., adjustment plates 240-1, 240-1) are optionally pivotallycoupled to one or more side plates 220, e.g., by a pivotal coupling 255.

The adjustment arm 230 optionally comprises a plurality of gear teeth232. The gear teeth 232 are optionally concentrically arranged about theopening 223. The gear teeth 232 are optionally configured (e.g., sized,spaced, etc.) to engage one or more gear teeth 242 of adjustment plate240 such that pivotal movement of the side plate 220 in a firstdirection causes pivotal movement of the adjustment plate 240, e.g.,about pivotal coupling 255. Gear teeth 242 are optionally concentricallyarranged about the pivotal coupling 255. One or more adjustment arms 230optionally support and/or are coupled to a platform 250.

Spring 300 optionally comprises a torsion spring such as a torsionspring model available from Rosta in Hunzenschwil, Switzerland. Thespring 300 is optionally supported on platform 250. The spring 300 isoptionally secured to platform 250, e.g., by one or more braces 253(e.g., braces 253 a, 253 b).

Belt engagement assembly 400 optionally comprises an arm 410 which isoptionally coupled to spring 300 (e.g., removably coupled by one or morefasteners 310) such that pivotal movement of arm 410 relative toplatform 250 is resiliently resisted by the spring 300. The arm 410optionally comprises and/or supports a plate 415. The plate 415optionally rollingly supports a pulley 420. The pulley 420 is optionallyrollingly supported on a pivotal support 425 (e.g., bearing, bushing,spacer, etc.). The pivotal support 425 is optionally coupled to plate415 and/or an additional plate 440 by a shaft support 430. In operation,the pulley 420 optionally engages (e.g., applies a force to, rollinglyengages, etc.) the belt 44.

Referring to FIGS. 6A, 6B, and 6C, the tensioning assembly 100 isillustrated a low position, a high position, and a desired position,respectively. The tensioning assembly 100 is optionally securable in aposition by tightening a fastener assembly 229 to secure adjustmentplate 240 to side plate 220. In some embodiments, the fastener assembly229 is extended (e.g., prior to positional adjustment) through openingsin the plates 220, 240 including a slot 227 in the plate 220. Thefastener assembly 229 is optionally movable within the slot 227 which isoptionally circumferentially arranged around pivotal coupling 225. Theradial extent of slot 227 optionally limits positioning high and lowpositions of the tensioning assembly 100. It should be appreciated thatan operator may use one hand to manipulate the adjustment arm 230 andanother hand to tighten and/or loosen the fastener assembly 229. In someembodiments, an alignment plate 320 is coupled to the spring 300 suchthat the alignment plate 320 pivots with the adjustment arm 410. In thedesired position, a lower edge 322 of alignment plate 320 is optionallyaligned with the platform 250. It should be appreciated in light of theforegoing that the angle of alignment plate 320 may serve as a visualindicator (e.g., to an operator, maintenance personnel, etc.) of thetension in belt 44.

Referring to FIG. 7 , another embodiment of a tensioning assembly 100′is illustrated in which a visual indication of the tension in belt 44 isindicated by an indicator 248 on adjustment plate 240′. The indicator248 is optionally visible on the view of FIG. 7 (e.g., from a positionadjacent to the assembly) through an opening 228 provided in side plate220. A visual indicator V is optionally provided at or adjacent toopening 228 for visual alignment of the indicator 248.

In various embodiments, the tensioning assembly 100 may be operablycoupled to other types of vibratory classifiers (e.g., incline screens,vibratory feeders, etc.).

Ranges recited herein are intended to inclusively recite all values andsub-ranges within the range provided in addition to the maximum andminimum range values. Headings used herein are simply for convenience ofthe reader and are not intended to be understood as limiting or used forany other purpose.

Although various embodiments have been described above, the details andfeatures of the disclosed embodiments are not intended to be limiting,as many variations and modifications will be readily apparent to thoseof skill in the art. Accordingly, the scope of the present disclosure isintended to be interpreted broadly and to include all variations andmodifications within the scope and spirit of the appended claims andtheir equivalents. For example, any feature described for one embodimentmay be used in any other embodiment.

1. A vibratory screen comprising first and second sidewalls and at leasta first classifying deck supported between the sidewalls, and aneccentric shaft operably coupled to the sidewalls in order to vibratethe sidewalls and the first classifying deck, the vibratory screencomprising: a motor; a belt driven by said motor, said belt operablycoupled to the eccentric shaft; a belt tensioning assembly configured toadjust a tension in said belt, the tensioning assembly comprising: asupport bracket; a belt engagement assembly operably engaging said belt;a torsion spring, said torsion spring operably coupling said beltengagement assembly to said support bracket, said torsion spring mountedto a spring support; an adjustment arm operably coupled to said supportbracket and said spring support, a position of said adjustment arm beingadjustable by a user, wherein adjustment of said position of saidadjustment arm adjusts a tension in said torsion spring; and a fastenerremovably coupling said adjustment arm, wherein tightening of saidfastener secures said position of said adjustment arm.
 2. The vibratoryscreen of claim 1, wherein said adjustment further comprising a visualindicator, said visual indicator indicating said tension in said torsionspring.
 3. The vibratory screen of claim 2, wherein said visualindicator comprises said spring support, said spring support beingaligned with a portion of said support bracket at a desired tension. 4.The vibratory screen of claim 2, wherein said visual indicator comprisesa feature of an adjustment plate, said adjustment plate being operablycoupled to said adjustment arm.
 5. The vibratory screen of claim 1,wherein said support bracket is mounted to a motor mount of the screen.6. The vibratory screen of claim 1, wherein said belt tensioningassembly further comprises: an adjustment plate, said adjustment plateoperably engaging said adjustment arm, said adjustment plate coupled tosaid spring support.
 7. The vibratory screen of claim 1, wherein saidbelt engagement assembly comprises: an arm coupled to said torsionspring; and a pulley rollingly supported on said arm, said pulleyrollingly engaging said belt.
 8. The vibratory screen of claim 2,wherein said belt engagement assembly comprises: an arm coupled to saidtorsion spring; and a pulley rollingly supported on said arm, saidpulley rollingly engaging said belt.
 9. The vibratory screen of claim 5,wherein said belt engagement assembly comprises: an arm coupled to saidtorsion spring; and a pulley rollingly supported on said arm, saidpulley rollingly engaging said belt.
 10. The vibratory screen of claim1, wherein said motor comprises an electric motor, and wherein said beltcomprises a v-belt.
 11. A tensioning assembly for use with a vibratoryscreen comprising first and second sidewalls and at least a firstclassifying deck supported between the sidewalls, and an eccentric shaftoperably coupled to the sidewalls in order to vibrate the sidewalls andthe first classifying deck, a motor, a belt driven by the motor andoperably coupled to the eccentric shaft, wherein the tensioning assemblyis adapted to adjust a tension in the belt, the tensioning assemblycomprising: a support bracket; a belt engagement assembly configured tooperably engage the belt; a torsion spring, said torsion spring operablycoupling said belt engagement assembly to said support bracket, saidtorsion spring mounted to a spring support; an adjustment arm operablycoupled to said support bracket and said spring support, a position ofsaid adjustment arm being adjustable by a user, wherein adjustment ofsaid position of said adjustment arm adjusts a tension in said torsionspring; and a fastener removably coupling said adjustment arm, whereintightening of said fastener secures said position of said adjustmentarm.
 12. The vibratory screen of claim 11, wherein said adjustmentfurther comprising a visual indicator, said visual indicator indicatingsaid tension in said torsion spring.
 13. The vibratory screen of claim12, wherein said visual indicator comprises said spring support, saidspring support being aligned with a portion of said support bracket at adesired tension.
 14. The vibratory screen of claim 12, wherein saidvisual indicator comprises a feature of an adjustment plate, saidadjustment plate being operably coupled to said adjustment arm.
 15. Thevibratory screen of claim 11, wherein said support bracket is mounted toa motor mount of the screen.
 16. The vibratory screen of claim 11,wherein said belt tensioning assembly further comprises: an adjustmentplate, said adjustment plate operably engaging said adjustment arm, saidadjustment plate coupled to said spring support.
 17. The vibratoryscreen of claim 11, wherein said belt engagement assembly comprises: anarm coupled to said torsion spring; and a pulley rollingly supported onsaid arm, said pulley rollingly engaging said belt.
 18. The vibratoryscreen of claim 12, wherein said belt engagement assembly comprises: anarm coupled to said torsion spring; and a pulley rollingly supported onsaid arm, said pulley rollingly engaging said belt.
 19. The vibratoryscreen of claim 15, wherein said belt engagement assembly comprises: anarm coupled to said torsion spring; and a pulley rollingly supported onsaid arm, said pulley rollingly engaging said belt.